Compound of plasticizers for the water dispersability of resins

ABSTRACT

Compound of plasticizers for the water dispersability of diol diarylate-type resins, characterized because it contains a high amount of diol monoarylates and optionally triol mono- or diarylates.

PURPOSE OF THE INVENTION

[0001] Compound of plasticizers based on a compound of diol or triol monoesters and diesters with benzoic acid and with a methylbenzoic acid, for use as an additive for adhesives applied in hydrophylous mediums.

BACKGROUND TO THE INVENTION

[0002] The use of dipropylenglycol or diethylenglycol ditoluates or dibenzoates and their compounds, and their use as plasticizers is documented in technical literature since last century. For example, the following publications describe the use as a plasticizer of diethylenglycol dibenzoate (DDB), triethylenglycol dibenzoate (TDB), diethylenglycol ditoluate (DDT), and triethylenglycol ditoluate (TDT) or their compounds: U.S. Pat. No. 2,070,331 (1936); UK 496,574 (1936); U.S. Pat. No. 2,585,448 (1948); UK 815,991 (1956); U.S. Pat. No. 2,956,978 (1960); UK 1,321,383 (1971); U.S. Pat. No. 3,874,985 (1973); Jpn Tokkyo Koho 81 00,304 (1975); A. V. Bailey et al., J.Am.Oil.Chem.Soc 1976, 53(5), 176-178; W. D. Arendt (Velsicol Chemical Corporation), Tech.Pap. 1979, 25, 410-412; U.S. Pat. No. 4,277,387 1981; U.S. Pat. No. 4,331,579 (1982); U.S. Pat. No. 4,336,166 (1982); U.S. Pat. No. 4,444,933 (1982); EPO 0 157 426 (1984); EPO 0 234 710 (1987); Fed.Regist. 1987 52(4) 527-530; U.S. Pat. No. 4,767,813 (1988); U.S. Pat. No. 4,818,779 (1989).

[0003] The plasticizer mentioned in a number of the above documents, since at least 1982, is Benzoflex, trademark of Velsicol Chemical Corporation to denominate a range of plasticizers with a composition of DDB and TDB compounds. There are other trademarks using the same range of compounds or equivalents of the same polyglycol polyesters, such as K-Flex, owned by Furam Chemicals Ltd. The use as plasticizers of arylic diesters of other glycols, such as propylenglycol derivatives, is also described in literature.

[0004] There are two chemico-physical reasons:

[0005] 1. a good plasticizer must be liquid at room temperature,

[0006] 2. the polymer to be plasticized (such as vinyl or acrylic-type polymers) is water-repellent that recommend that the plasticizer should be a compound of arylic glycol diesters and, sometimes, triol triesters. In a document such as U.S. Pat. No. 5,676,742, when a compound with diethylenglycol and dipropylenglycol monoesters, together with the corresponding diesters, is described, it is to highlight that the advantage is not as a plasticizer, but as an additive resistant to the growth of mildew.

[0007] The fact that the most popular plasticizers in industry are liquid diesters is because:

[0008] 1. Processes in which a plasticizer is involved, are conducted in totally water-repellent mediums, such as poly(vinyl chloride) or poly(methyl acrylate). The nature of these water-repellent mediums means that the presence of monoesters deteriorates the technical properties of the plasticizer (for example, see U.S. Pat. No. 2,956,978).

[0009] 2. The required flexibility in the final plastic is reduced if the plasticizers become solid at room temperature. A liquid compound of plasticizers in which at least one of its components of over 20% becomes solid at room temperature, has disadvantages in certain cases, such as when it is used with adhesives to join parts in motion.

[0010] The highly water-repellent nature of the polymers to be plasticized means that the dispersability in water of these polymers is very short. This is demonstrated in recent generally vinyl or acrylic polymer-based industrial adhesives applied in aqueous mediums, as during industrial use of usual plasticized polymer formulae with DDB or TDB compounds, an aqueous phase and another water-repellent phase are quickly separated, rapidly causing a lack of homogeneity in these suspensions. This results in a faulty application of the adhesive leading to less adhesive power.

DESCRIPTION OF THE INVENTION

[0011] With the compound of plasticizers for the water dispersability of resins, that is the purpose of this invention, the inconvenience of the separation of phases during the industrial application of coats or seals in a water or simply hydrophylous medium, is eliminated.

[0012] The invention consists of a compound of diol or triol arylic monoesters, as the vehicle plasticizer of hydrophylous properties, together with the aforementioned arylic diesters that are water-repellent but easily miscible with the monoester molecules. It has been discovered that the monoesters of these polyoles are excellent molecules to intervene sufficiently in the solvatation/dispersion in water of the polymer water-repellent molecules.

[0013] The high polarity of the plasticizer compound of the invention enables dispersions with eight-hour stability to be achieved. This time period is a significant improvement in the industrial handling of dispersions.

[0014] Part of the invention includes the option of having a slight percentage of an arylic ester of a triol, such as 1,1,1,-trimethylolpropane, present in the plasticizer compound. This component also increases the average molecular weight of the plasticizer compound, resulting in a favorable reduction of volatility and migration. DESCRIPTION OF THE PLASTICIZER COMPONENTS WHICH ARE THE PURPOSE OF THE INVENTION Group 1. Glycol monoarylates. Ar-COO-R₂-OH Group 2. Glycol diarylates. Ar-COO-R₂-OCO-AR Group 3. Triol monoarylates. Ar-COO-(R3)(OH)₂ Group 4. Triol diarylates. (Ar-COO)₂-(R3)-OH

[0015] where Ar—COO— represents any of the following functional groups: Benzoate, 1-methylbenzoate, 2-methylbenzoate and 3-methylbenzoate.

[0016] Glycols can be: Diethylenglycol, triethylenglycol, dipropylenglycol, tripropylenglycol, neopenthylglycol.

[0017] Triols can be: Glycerin, 1,1,1-trimethylolethane, 1,1,1,-trimethylolpropane, 1,2,6-hexanotriol.

PREFERENTIAL MANUFACTURE OF THE INVENTION

[0018] Monoesters, diesters and their compounds are prepared following any of the existing methods, such as by mixing the pure chemicals or by joint sterification of the polyalcohols. Proportions in compounds are expressed in weight %.

[0019] Formula 1.

[0020] Diethylenglycol monobenzoate . . . 10%

[0021] Diethylenglycol monotoluate . . . 2%

[0022] Dipropylenglycol monobenzoate . . . 10%

[0023] Dipropylenglycol monotoluate . . . 1%

[0024] 1,1,1-trimethylolethane monobenzoate . . . 3%

[0025] Diethylenglycol dibenzoate . . . 35%

[0026] Diethylenglycol ditoluate . . . 1%

[0027] Dipropylenglycol dibenzoate . . . 35%

[0028] Dipropylenglycol ditoluate . . . 2%

[0029] 1,1,1-trimethyloletane dibenzoate . . . 1%

[0030] Formula 2.

[0031] Diethylenglycol monobenzoate . . . 10%

[0032] Diethylenglycol dibenzoate . . . 40%

[0033] Dipropylenglycol monobenzoate . . . 5%

[0034] Dipropylenglycol dibenzoate . . . 20%

[0035] Triethylenglycol monobenzoate . . . 5%

[0036] Triethylenglycol dibenzoate . . . 20%

[0037] Formula 3.

[0038] Diethylenglycol monobenzoate . . . 10%

[0039] Diethylenglycol dibenzoate . . . 50%

[0040] Dipropylenglycol monobenzoate . . . 10%

[0041] Dipropylenglycol dibenzoate . . . 30%

[0042] Formula 4.

[0043] Diethylenglycol monobenzoate . . . 10%

[0044] Diethylenglycol dibenzoate . . . 38%

[0045] Dipropylenglycol monobenzoate . . . 5%

[0046] Dipropylenglycol dibenzoate . . . 20%

[0047] Triethylenglycol monobenzoate . . . 5%

[0048] Triethylenglycol dibenzoate . . . 20%

[0049] 1,1,1-trimethylolethane monobenzoate . . . 1.5%

[0050] 1,1,1-trimethylolethane dibenzoate . . . 0.5%

[0051] A typical result of those obtained with the new plasticizers is indicated in the following graph:

[0052] The upper line of this graph shows, according to the seconds elapsed since the application of the adhesive, the adhesive power reached by one of the marketed water adhesives when the formula 2 plasticizer is used.

[0053] The bottom line of the graph shows the adhesive power reached by the same water adhesive under the same conditions, when the plasticizer is one of those currently used for this type of adhesive.

[0054] The improved adhesive power is because of the greater dispersability of the plasticizer in water caused by the presence of hydrophylous hydroxyl groups. 

1. Compound of plasticizers for the water dispersability of diol diarylate-type resins, characterized because it contains a high quantity of diol monoarylates and optionally triol mono- or diarylates.
 2. Compound of plasticizers in accordance with claim 1, characterized because the arylic acids used for sterification are one or several of the following: Benzoic acid, 1-methylbenzoic acid, 2-methylbenzoic acid, 3-methylbenzoic acid.
 3. Compound of plasticizers in accordance with claim 1, characterized because the diols used for sterification are one or several of the following: Diethylenglycol, triethylenglycol, dipropylenglycol, tripropylenglycol, neopenthylglycol.
 4. Compound of plasticizers in accordance with claim 1, characterized because the triols optionally used for sterification are one or several of the following: Glycerin, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, 1,2,6-hexanotriol.
 5. Compound of plasticizers in accordance with claim 1, characterized by the simultaneous presence of at least two diesters and two monoesters.
 6. Compound of plasticizers in accordance with claim 1, characterized because the weight proportion of the total diol monoarylates is between 5% and 35% of the total final compound.
 7. Compound of plasticizers in accordance with claim 1, characterized because the weight proportion of the total diol diarylates is between 50% and 80% of the total final compound.
 8. Plasticizers in accordance with claim 1, characterized because the weight proportion of the total triol monoarylates is between 0% and 10% of the total final compound.
 9. Plasticizers in accordance with claim 1, characterized because the weight proportion of the total triol diarylates is between 0% and 5% of the total final compound.
 10. Plasticizers in accordance with claim 1, characterized because the hydroxyl index, determined according to standard ASTM E 222 (94), is between 35 and
 70. 